Source material The Traitor

Sources used in this series include:

Hans Fredrik Dahl “En norsk tragedie” (“A Norwegian Tragedy”)
Per Jahr “Tre skritt bak” (“Three steps behind”)
Maria Quisling “Diary and other notes”
Harald Breen “I Malstrømmen”
Johan Nygaardsvold “Diary”
Vidkun Quisling “Universism”
Arve Juritzen “Vidkun Quisling privat”
Oddvar Høidal “Quisling: A study in treason”
Full transcript of the Trial Against Vidkun Quisling (original)
Berit Nøkleby “Terboven - Hitler’s mann i Norge”
Various articles in SNL.no, Aftenposten.no, VG.no and ABC Nyheter
For background reference: “Quisling’s Koffert” Podcast, NRK and “Vidkun Quisling - et liv” TV series, NRK